Our tasks are Great Books, not Great(TM) Music, but I can't recommended these CBC podcasts on the Beethoven Symphony enough. The conductor of the Vancouver Symphony sits down at the piano and walks us through all the themes, etc. of each symphony, gently prodded by the awesomely Anglo-Canadian-accented host. It helps if you actually know the symphonies somewhat in advance (I'm looking at you, Symphony #4), but I had to drive around hither and yon today doing meetings and they were great entertainment in the car.